1. Field of the Invention
The invention generally relates to transmission control in a wireless communications device, and more particularly, to wireless communications devices and methods for transmission control in a wireless communications device associated with different radio access technologies (RATs).
2. Description of the Related Art
In a typical mobile communications environment, user equipment (UE) may communicate voice and/or data signals with one or more service networks via cellular stations of the service networks. The wireless communications between the UE and the service networks may be in compliance with various radio access technologies (RATs), such as the Global System for Mobile communications (GSM) technology, General Packet Radio Service (GPRS) technology, Enhanced Data rates for Global Evolution (EDGE) technology, Wideband Code Division Multiple Access (WCDMA) technology, Code Division Multiple Access 2000 (CDMA 2000) technology, Time Division-Synchronous Code Division Multiple Access (TD-SCDMA) technology, Worldwide Interoperability for Microwave Access (WiMAX) technology, Long Term Evolution (LTE) technology, Universal Mobile Telecommunications System (UMTS) technology, short range wireless technology such as WLAN (e.g., WiFi) technology, Bluetooth technology, and others.
Currently, the UE may have multiple wireless interfaces for different RATs. For example, the UE may have a WiFi interface for performing WiFi communication and a LTE interface for performing LTE communication. In many situations it is necessary to operate two or more wireless interfaces simultaneously. Depending on the operating frequencies of the wireless interfaces, the UE can experience interference due to the simultaneous operation of the wireless interfaces. Specifically, the transmitting signals on one interface results in interference being experienced in the reception of signals on the other interface. For example, for a UE having both a WiFi interface and a LTE interface for simultaneously supporting WiFi and LTE communications, a WiFi station (STA) may not able to receive data from a WiFi access point (AP) during the LTE uplink transmission period due to the LTE uplink interference so that the WiFi data rate may be dropped. Therefore, the interference between these two technologies operating in the same UE creates challenges for the coexistence of the corresponding wireless interfaces of that UE.